Rotary solenoid ratchet switch

ABSTRACT

A rotary solenoid-ratchet switch. Upon energization of the solenoid, a drive pawl is moved into engagement with a tooth of a ratchet. As the drive pawl moves through a rotary stroke, it also moves axially. The pawl imparts only a rotary motion to the driven ratchet. When the drive pawl ends its stroke, it is prevented from being disengaged from the driven ratchet by a stop. Upon return of the pawl to its starting position, it is cammed out of engagement with the ratchet by a cam arm. An interrupting switch for the rotary solenoid is operated by movement of the pawl.

[ Oct. 9, 1973 ROTARY SOLENOID RATCHET SWITCH [75] Inventors: Frederick M. Ford, Carpentersville; Robert L. Harvey, Dundee, both of I11.

[73] Assignee: Oak Electro/Netics Corp., Crystal Lake, Ill.

[22] Filed: Jan. 19, 1972 [21] Appl. No.: 218,954

2,812,453 11/1957 Mastney 74/126 2,820,370 l/l958 Dolesh et al 3,320,822 5/1967 Tatom 74/126 Primary ExaminerCharles J. Myhre Assistant Examiner-Wesley S. Ratliff, Jr. Attorney-Howard T. Markey et a1.

[5 7] ABSTRACT A rotary solenoid-ratchet switch. Upon energization of the solenoid, a drive pawl is moved into engagement with a tooth of a ratchet. As the drive pawl moves through a rotary stroke, it also moves axially. The pawl imparts only a rotary motion to the driven ratchet. When the drive pawl ends its stroke, it is prevented from being disengaged from the driven ratchet by a stop. Upon return of the pawl to its starting position, it is cammed out of engagement with the ratchet by a cam arm. An interrupting switch for the rotary solenoid is operated by movement of the pawl.

6 Claims, 4 Drawing Figures PATENTEI] UN 9 SHEET 2 [IF 2 1 ROTARY SOLENOID RATCI-IET SWITCH SUMMARY OF THE INVENTION This invention is concerned with a rotary solenoidratchet switch and more particularly with a switch in which the ratchet driving pawl is disengaged from the ratchet upon deenergization of the solenoid.

An object of this invention is a rotary solenoidratchet switch in which the driven ratchet shaft may be rotated by an external force in either direction when the solenoid is deenergized.

Another object is a rotary solenoid-ratchet switch which controls the flow of electrical current to the solenoid.

Another object is a rotary solenoid-ratchet switch in which the pawl is prevented from being disengaged from the ratchet when it completes its stroke.

Other objects may be found in the following specification, claims and drawings.

BRIEF DESCRIPTION'OF THE DRAWINGS FIG. 1 is a partial side elevational view of a rotary solenoid-ratchet switch of this invention with some parts. broken away and others shown in cross-section;

FIG. 2 is a view taken along line 2-2 of FIG. 1;

FIG. 3 is a view taken along line 33 of FIG. 1; and

FIG. 4 is a view taken along line 4-4 of FIG. 1 and showing various positions of the pawl in broken lines.

DESCRIPTION OF THE PREFERRED EMBODIMENT A switch embodying the teachings of the invention is shown in the drawings. The switch includes a rotary solenoid 11 having a solenoid output shaft 13 to which is affixed a yokelS. The yoke includes an integral arm 17 havingan inclined upstanding portion 19 and a laterally extending portion 21. A second arm 23 is also formed integrally with the yoke and is located generally diametrically to the arm 17. This arm functions as a support for the yoke return spring 25. The return spring is U-shaped and the opposite end thereof engages a support column 27 mounted on the solenoid 11. A similar support column 29 is mounted on the solenoid in a location diametrically opposite of the column 27.

A drive pin 33 is attached to the laterally extending portion 21 of the arm 17. A pawl 35 is rotatably mounted on the drive pin and is biased in the direction of a ratchet gear 37 by a spring 39. The ratchet gear is affixed to a ratchet drive shaft 41 which is aligned with and spaced from the solenoid output shaft 13. The ratchet gear 37 and drive shaft 41 are supported on a switch mounting plate 43 which is supported on the columns 27 and 29.

A solenoid interrupter switch stator 47 of generally annular shape is supported on columns 49,51 which extend from and are supported on the switch mounting plate 43. A solenoid interrupter switch rotor 53 has a hub 55 which fits into the central opening 57 of the stator 47. The hub includes a central opening 59 which receives the ratchet drive shaft 41 in rotatable engagement therewith.

The rotor 53 includes an elongated slot 63 near the free end thereof which receives an end of the drive pin 33 to provide a lost motion connection between the drive pin and the rotor.

Arcuate rings 65 and 67 of conductive material are mounted on the rotor hub 55 by means of integral tabs 69 which fit into spaced slots 71 formed in the hub. Radially projecting portions 73,75 are formed as parts of the rings 65,67 near one of the sets of contiguous ends thereof.

Terminals 77,79 and 81,83 of electrical conductive material are affixed to the solenoid interrupter switch stator 47. Terminals 77 and 83 extend radially inwardly farther than the terminals 79 and 81 to contact the main portions of the arcuate rings and 67 while terminals 79 and 81 are positioned to contact only the radially projecting portions 73,75 of the rings.

The switch mounting plate 43 includes an integral L- shaped arm 89 having a stop portion 91 which extends from the mounting plate towards the rotary solenoid 11. The stop portion includes an inner wall 92 which is inclined tangentially relative to the ratchet gear 37 so that its end adjacent to the pawl 35 is spaced a greater distance from the ratchet gear than is its opposite end.

The pawl 35 includes a nose portion 95 which engages the teeth 97 of the ratchet gear 37 and a tail portion 99 which is positioned on the opposite side of the drive pin 33 from the nose portion 95. Adjacent the nose portion, the pawl has a rounded portion 100 of controlled radius. A cam means 101 is also formed integrally with the switch mounting plate 43 and is positioned to engage the tail portion of the pawl when the pawl is in the position it occupies when the solenoid 11 is deenergized.

The use, operation and function of this invention are as follows:

When the rotary solenoid 11 is deen'ergized, the cam means 101 attached to the switch mounting plate 43 engages the tail portion 99 of the pawl 35 moving the nose portion 95 of the pawl out of engagement with the teeth 97 of the ratchet 37. With the pawl disengaged, the ratchet gear 37 and ratchet drive shaft 41 may be rotated freely in either clockwise or counterclockwise directions by an exterior force applied to the ratchet drive shaft.

When the pawl is disengaged from the ratchet, the terminal 81 of the solenoid interrupter switch contacts the radial projection of the arcuate conducting ring 67 providing a circuit for supplying current to the solenoid. When current is applied to the solenoid, the solenoid output shaft 13 both rotates and moves axially outwardly of the solenoid. In this embodiment of the invention, the rotation of shaft 13 will be in a counterclockwise direction as viewed in FIGS. 2, 3 and 4 of the drawings. As the shaft 13 rotates, the yoke 15 is carried with it. The yoke carries the drive pin 33. The rotation of the drive pin moves the pawl tail portion 99 out of contact with the cam means 101 allowing the spring 39 to bias the nose of the pawl into contact with the teeth 97 of the ratchet gear 37. Due to the movement of the drive pin 33 and the influence of the spring 39, the pawl 35 undergoes both radial and tangential movement. As it contacts the teeth 97 of the ratchet 37, it imparts only a rotational movement to the ratchet.

Initial movement of the drive pin 33 will not affect the solenoid interrupter switch rotor 53 since the drive pin is moving freely in the elongated slot 63. However, when the drive pin reaches the end of this slot, it engages the rotor 53 and urges it to rotate in a counterclockwise direction as viewed in FIG. 4. Movement of the rotor 53 moves the interrupter switch conductor rings 65 and 67 to break contact between the ring 67 and the terminal 81 and to make contact between the terminal 79 and the radial projection 73 of the ring 65, thus completing a circuit between the terminals 77 and 79.

When the shaft 13 of the rotary solenoid 11 reaches the end of its stroke, the nose portion 95 of the pawl 35 will be in the position shown in FIG. 4. In this position, the pawl will be located between the ratchet gear 37 and the wall 92 of the stop portion 91 of the arm 89. The stop portion acts to prevent disengagement of the pawl from the ratchet due to inertia of the ratchet.

During rotation of the yoke 15 and the solenoid output shaft 13, the return spring 25 was tensioned. When the pawl reaches the end of its stroke and the current is shut off to the solenoid, the return spring 25 biases the pawl to its starting position. As the pawl moves to its starting position along with the yoke 15, the solenoid interrupter switch rotor 53, after a delay due to lost motion connection, also moves to its starting position, interrupting the circuit between terminals 77 and 79 and completing the circuit between the terminals 81 and 83. Due to the incline of the wall 92 of the stop 91 and the controlled radius of the rounded portion 100 of the pawl 35, the pawl, upon retraction to its starting position, will clear the wall 92. As the pawl moves into its starting position, its tail portion 99 engages the cam means 101, moving the pawl nose out of contact with the ratchet teeth 97. Now, the rotary solenoid is in its deenergized starting position.

Whereas, the preferred form of the invention has been described and shown, it should be understood that there are modifications, alterations and changes which may be made without departing from the teachings of the invention. Therefore, the scope of the invention should be only limited by the claims attached hereto.

We claim:

1. A rotary solenoid-ratchet switch including:

a rotary solenoid having an output shaft which rotates and moves axially upon energization of said solenoid,

a yoke affixed to said output shaft and having a laterally extending arm,

means biasing said yoke and affixed output shaft to the de-energized position of said solenoid,

a drive pin mounted on said laterally extending arm,

a pawl mounted on said drive pin,

a ratchet gear affixed to a shaft aligned with said rotary solenoid output shaft,

means biasing said pawl towards engagement with said ratchet gear, and

means for holding said pawl out of contact with said ratchet gear when said rotary solenoid is deenergized.

2. The switch of claim 1 further characterized in that said means to hold said pawl out of contact with said ratchet gear includes a projection of said pawl located on the opposite side of said drive pin from said ratchet engaging portion of said pawl and cam means positioned to engage said projection when said yoke is returned to the deenergized position of said rotary solenoid.

3. The switch of claim 1 further characterized in that an arm is rotatably mounted on said ratchet gear shaft, the free end of said arm engages said drive pin with a lost motion connection, and switch means for completing and interrupting circuits to said rotary solenoid are at least partially carried by said arm.

4. The switch of claim 3 further characterized in that said lost motion connection includes an elongated slot formed in the free end of said arm.

5. The switch of claim 1 further characterized in that stop means are provided to prevent disengagement of said pawl from said ratchet gear when said pawl reaches the end of its stroke.

6. The switch of claim 5 further characterized in that said stop means includes an arm positioned radially of said ratchet gear and said pawl at a location where said pawl reaches the end of its stroke with the arm being closely located radially outward of said pawl. 

1. A rotary solenoid-ratchet switch including: a rotary solenoid having an output shaft which rotates and moves axially upon energization of said solenoid, a yoke affixed to said output shaft and having a laterally extending arm, means biasing said yoke and affixed output shaft to the deenergized position of said solenoid, a drive pin mounted on said laterally extending arm, a pawl mounted on said drive pin, a ratchet gear affixed to a shaft aligned with said rotary solenoid output shaft, means biasing said pawl towards engagement with said ratchet gear, and means for holding said pawl out of contact with said ratchet gear when said rotary solenoid is de-energized.
 2. The switch of claim 1 further characterized in that said means to hold said pawl out of contact with said ratchet gear includes a projection of said pawl located on the opposite side of said drive pin from said ratchet engaging portion of said pawl and cam means positioned to engage said projection when said yoke is returned to the deenergized position of said rotary solenoid.
 3. The switch of claim 1 further characterized in that an arm is rotatably mounted on said ratchet gear shaft, the free end of said arm engages said drive pin with a lost motion connection, and switch means for completing and interrupting circuits to said rotary solenoid are at least partially carried by said arm.
 4. The switch of claim 3 further characterized in that said lost motion connection includes an elongated slot formed in the free end of said arm.
 5. The switch of claim 1 further characterized in that stop means are provided to prevent disengagement of said pawl from said ratchet gear when said pawl reaches the end of its stroke.
 6. The switch of claim 5 further characterized in that said stop means includes an arm positioned radially of said ratchet gear and said pawl at a location where said pawl reaches the end of its stroke with the arm being closely located radially outward of said pawl. 